The Government Accountability Board said politicians could use campaign funds to pay legal fees for investigations that are both civil and criminal, but not for a matter that is "purely a criminal one," Wisconsin State Journal reported Wednesday.

The GAB found that legal fees paid from a campaign or legal defense fund "both appear to be appropriate because the investigation and defense activities cannot currently be parsed between what may be civil and what may be criminal."

"If that changes, then the committee may only pay for costs incurred in a civil context and a defense fund may be used only to pay costs in a criminal context," the opinion said.

The opinion does not say which campaign committee requested the ruling, and a GAB spokesman refused identify it.

Nothing in the opinion indicates whether it is related to the secret investigation involving Wisconsin Republicans.

Under Wisconsin finance laws, government officials can raise money for legal defense only if they're being investigated for or charged with violating campaign finance or elections laws.

The ruling released Tuesday is the GAB's first on the subject of legal fees paid with campaign funds. It also comes days after Walker's campaign reported paying a law firm $86,000 and a state appeals court refused to halt the secret, so-called John Doe investigation.